Important lessons to take away from BNP Paribas' record settlement

French bank BNP Paribas agreed to plead guilty to criminal charges and pay nearly $9 billion for violating U.S. economic sanctions Monday. Federal officials said the settlement marked the first time a major bank agreed to "large-scale systematic violations of U.S. economic sanctions," according to USA Today.

Shares of BNP Paribas rose 4% after BNP's CFO Lars Machenil said on a conference call that the bank would still pay a dividend to shareholders and the penalty would not endanger its capital cushion or curtail important operations around the world, notes Yahoo Finance's Mike Santoli.

Also, "it's been so known for so long that there was going to be a fine in this area of $9 billion that the market basically got accommodated to the idea," says Santoli. Because investors knew the blow was coming they were able to "flinch in advance," and now that the news is out there and the effect calculable investors are okay with it.

BNP Paribas, the largest bank in France, made $6.5 billion in profits last year and has $2.5 trillion in assets.

U.S. authorities began investigating BNP Paribas in 2010. Officials dug up evidence that the bank had processed (and deliberately disguised) financial transactions for Iran, Sudan and Cuba -- countries that are blacklisted by the U.S. government.

Finally -- a real lesson to come out of this: be careful what you put in your emails. "Once again, excessively honest emails about bad business practices really was what you could BNP on with this," says Santoli.